JPS637794Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an antifreeze device for forced air water heaters.

For water heaters used in cold regions,
When the hot water supply is stopped, the temperature of the atmosphere or the temperature of the accumulated water is detected by a temperature sensor such as a thermistor installed near the heat collector, and when the temperature drops to freezing, an anti-freeze valve is used to reduce the temperature to 5℃ even in winter. Either discharge tap water, etc. with a water temperature of ~6℃ into the container to prevent the temperature from decreasing, or
The common method is to open the water drain valve and drain the accumulated water inside the vessel, but these methods waste water resources and have problems in disposing of the drained water.Also, there is also a method of heating the accumulated water with a heater to raise its temperature. However, localized heating is insufficient to prevent the entire system from freezing, and heating the entire system has the disadvantage of large electrical heat loss.

This idea eliminates the shortcomings of conventional anti-freeze methods, and is effective in preventing damage to the vessel due to freezing as a hot air convection method using the forced air fan of forced air water heaters. It was designed so that it could be carried out.

One embodiment will be described below with reference to the drawings.

In the drawing, reference numeral 1 denotes a forced air fan for a forced air water heater. An electric heater 3 is installed at the air outlet 2 of the forced air fan 1, and a temperature sensing element such as a thermistor (not shown) installed near a heat collector 4 controls the atmosphere. temperature or the temperature of accumulated water, etc., and the temperature is freezing temperature (e.g. 1℃~
When the temperature drops to around 2° C.), the electric heater 3 is energized and the forced air supply fan 1 is rotated at a low speed. The energization of the electric heater 3 and the low-speed rotation of the forced air supply fan 1 are automatically controlled via a control box using electrical signals from the temperature sensing element. The forced air supply fan 1 is rotated at high speed in conjunction with a water flow switch (not shown) or a water pressure responsive flasher 7 during normal use. In the figure, 5 is the sealed outer casing of the water heater, 6 is the air supply introduction path, 8 is the water supply pipe, 9 is the hot water outlet pipe,
10 is an exhaust stack, and 11 is a gas burner.

In the above configuration, when the temperature of the atmosphere or the temperature of the accumulated water drops to near the freezing temperature when hot water supply is stopped, this is sensed by the temperature sensing element, and at the same time, the electric heater 3 is energized and the forced air supply fan 1 is rotated at low speed. Since the cold air passes through the electric heater 3, warm air with a temperature necessary to prevent freezing can be obtained.
This air is sent into the outer casing 5 through the air supply introduction path 6 of the outer casing 5, and slowly convects inside the outer casing 5.
The water pressure-responsive flasher 7, heat collector 4, water supply pipe 8, and other containers installed inside the outer casing 5 are heated from the outside to prevent water stagnant inside them from freezing.

As explained above, this idea is simple: a heater is installed near the air outlet of the forced air fan, and when the atmosphere or water temperature drops below the set temperature, the heater is energized and the forced air fan is rotated at a low speed. With this structure, freezing prevention in cold regions can be performed economically and reliably, eliminating damage to forced air water heaters due to freezing, and also doubles safety.

[Brief explanation of the drawing]

The drawing is a schematic diagram showing an embodiment of this invention. 1... Forced air supply fan, 2... Air outlet, 3...
…heater.

Claims (1)

[Scope of utility model registration request] A forced air water boiler characterized in that a heater is provided near the air outlet of the forced air fan and the heater is energized when the atmosphere or water temperature drops below a set temperature and the forced air fan is rotated at a low speed. Antifreeze device for vessels.